morgan-config.js

const morgan = require('morgan');
const chalk = require('chalk');

// Create a custom token for morgan that applies color to log messages
morgan.token('colored-status', (req, res) => {
  // Customize the color based on the HTTP status code
  const status = res.statusCode;
  let color = 'green'; // Default to green for success

  if (status >= 400 && status < 500) {
    color = 'yellow'; // Yellow for client errors (4xx)
  } else if (status >= 500) {
    color = 'red'; // Red for server errors (5xx)
  }

  // Apply the color to the status code using chalk
  return chalk[color](status);
});

morgan.token('colored-ip', (req) => {
  const ip = req.ip; // IP address of the client
  const color = 'cyan'; // Color for IP address (e.g., cyan)
  return chalk[color](ip);
});

morgan.token('user-agent', (req) => {
  return req.get('user-agent'); // User-Agent header from the request
});

module.exports = morgan;